It is known to make hollow articles, especially bottles, by a blowing method, in that a hose extruded directly before by means of an extruder is blown into the desired hollow article using a blow mold. In this operation it is also known to extrude several hoses simultaneously which are blown into bottles with the aid of alternately working blow mold batteries. It is known, too, to finish a hose extruded by means of an extruder on rotary attachment machines working continuously or in a fixed-cycle operation, said hose being fed to said machines.
The production rate of these methods and machines is limited and is far from being equal to the throughput per capacity hour of the usual automatic racking plants. The throughput capacity of such automatic racking plants, for example, amounts to about 10,000 to 50,000 bottles per hour.
The invention is concerned with the problem of providing a method for the production of hollow articles, especially bottles, of thermoplastics, which allows for the construction of machines with an especially high production rate, so that also the throughput of the blowing machine constructed in accordance with the invention will approximately correspond with the throughput per hour of a racking plant. In addition, the invention is concerned with the problem of reducing the expenses in the manufacture of such bottles and to provide the conditions for small and quickly operating blowing machines which, in spite of high speeds, will be able to work essentially without vibrations.
It has already been proposed to supply tubular blanks open on both ends and made of thermoplastics to a bottle blowing machine and to heat these blanks in the blowing machine to forming temperature (welding temperature) and to inflate them to the desired shape. In order to solve the problem, the invention starts out from this known method.